C-clamp



Patented June 25, 1940 UNITED STATES PATENT OFFICE C-CLAMP Conrad J. Schroeder, vKansas City, Mo. Application December 30, 1936, Serial No. 118,330

6 Claims. v

bearing for the adjusting screw in the tubular My invention relates to clamps, and more para exceedingly strong in construction and which is complished by slotting the tubular bodyportion y5' so constructed that the adjusting means will not so that a leg 'of the C-shaped body portion passes be injured in any manner by heat produced by through said slot and the tubular member is a welding arc, or flame, and which will engage guided for longitudinal sliding movement relathe parts that are being clamped flatly so that tive to the C-shaped body portion. The screw- 10 there will be no possibility of the clamping jaws threaded member has screw-threaded engagel0 tilting relative to the material clamped nor of ment with one of the legsV of the C-shaped body the clamp slipping out of position due to any unportion, and furthermore, preferably, has a beareven engagement of the jaws with the work, or 'lng provided therefor in the inner face of the vany so-,called walking of the movable jaw on closed end wall of the tubular body portion of #l5 the work, as is the case with C-clamps now in one of the jaws of the clamp. An advantage of l5` use. l this construction is that due to the dat engage- More particularly my invention involvesy a ment of the jaws with the work, it is not necesclamp of the above mentioned character that sary to `open the cla-mp as widely to release the comprises a C-shaped, or yoke-like, body portion same from the work, as where a swiveled jaw is having a pair of legs, one of which provides a provided that tilts as it is being released. 20l

fixed jaw and the other of which provides means It is a further purpose of my invention to profor mounting a jaw that is movable relative to vide means for holding said screw-threadedadthe body portion, said movable jaw being so conjusting means from endwise movement relative structed as to have great strength and to engage to-thetubular body portion, which means com- 125 the work flatly without any possibility of lthe jaw prises a detachable member whereby the devic 25 getting out of line, or tilting, and which is furcan be readily assembled. I ther so constructed that the adjusting means as- Other objects and advantages of my invention Sociated therewith will not be exposed to the will appear as the dsecription of the drawing proame, or are, of welding apparatus, or similar ceeds. I desire to have it understood, however,

heat producing means. f that I do not intend to limit myself to the par- 30 It is a further purpose of-my invention to proticular details shown or described, except as devide a clamp of the above mentioned character, fined by the claims. in which the jaw that is movable relative -to the In the drawing: y C-shaped body portion comprises a housing for Fig. lis a view inside elevation of my improved Ithe adjusting means, being, preferably, made of C-clamp, partly broken away. 35

a tubular character with a closed end wall form- Fig. 2 is a section taken on the line 2 2 of ing one clam-ping jaw and with bearings pro- Fig.'1. vided therein for the adjusting means so that Fig. 3 is a section taken on the line 3 3 of said adjusting means is rotatable relative to said Fig.'1.

4o jaw, one of said bearing portions being, prefer- Fig. 4 is a fragmentary section taken on the 40 ably, provided at the opposite end of the tubular line 4-4 o f Fig. 2, but on an enlarged scale. body portionfrom the closed end forming the Fig. 5 is a fragmentary section taken on the clamping jaw. line 5-5 of Fig. 1, but on an enlarged scale, and

It is still another purpose of my invention to Fig. Gis a fragmentary section taken on the 'c5 provide a clamp of the above mentioned charline 6-6 of Fig. 2,on an enlarged'scale. v 45 acter in which the body portion of the clamp is Referring in detail to the drawing, my. impulled, or drawn, toward the tubular jaw memproved clamp comprises a C-shaped, or yokeber, instead of the tubular jaw member being like, body portion having the legs IU and H and pushedV toward the jaw carried by the body porthe connecting portion I2. The same may be 5o tion, during movement of the parts toward clampmade of any desired cross sectional shape, but is, 50 ing pOStOrl. this providing a tBYlSOn 011 the adpreferably, made of substantially T-shaped cross justing means, rather than a Compression theresection with a somewhat enlarged head portion I3 on, which will prevent bending of the adjustand an enlarged base portion I4 so as to make ing means, which is usually made in the form of the body portion ofthe clamp of considerable a screw. This is accomplished by providing a strength. The leg portion l0 is somewhat thick- 55 ticularly to adjustable C-clamps.

It is a purpose of my invention to provide a clamp of the above mentioned character that is jaw member and providing means for holding said tubular jaw member against rotation relative to the yoke-like body portion, this being acened and enlarged to provide a clamping jaw I5, which has a flat clamping face I6, while the leg II is provided with a rounded somewhat enlarged tubular end portion I1, which is provided with an internally screw-threaded opening I8.

Screw-threadedly engaging in the screwthreaded opening I8 is a screw-threaded adjusting member I9 made in the form of a screwthreaded stem having an enlarged end portion, or head, 2G, which may be of rectangular cross section, as shown in the drawing, and which is provided with a transverse opening 2l, through which the handle, or adjusting lever, 22 extends, the same being slidably mounted therein, as is common with such handle members, and is provided with enlargements, or heads, 23 at the ends` thereof to prevent disengagement of the same from the portion 20. The head portion 20 provides a shoulder, or abutment, at 24 on the adjusting member, while the screw-threads 25 on the screw-threaded stem I9 engage with the threads 26 in the opening provided in the tubular enlargement I1..

Mounted on the adjusting member is the tubular body portion 21 of a jaw member, which isI provided with a closed end wall 28, providing a ilat jaw portion that is adapted to cooperate with the jaw I El to clamp any desired work, that is to be engaged by the clamp therebetween. The member 21, as will be evident from Fig. 3, is circular in cross section, being of a tubular character, and it is obvious that the thickness of the material of the tubular portion 21 can be varied as desired to obtain the desired strength for the member 21. It is, of course, desirable that the member 21 `and the yoke-like body portion be of substantially the same strength so that neither of the two parts will be capable of damage by force exerted on the clamp by means of the handle 22 through the screw threaded adjusting member I9. It will also be noted, upon reference to Fig. 3, that a slot 29 is provided, extending longitudinally of the' member 21 that is of such width as to receive the enlarged portion I4 of the leg II of the body portion of the clamp therebetween so that said member 21 will be slidably engaged with said leg II of said body portion, or in other Words, that said body portion may slide lengthwise in the slot thus provided, so that said tubular body portion and said tubular member 21 will be held against relative rotation and will only be movable longitudinally relative to each other. l

Upon reference to Fig. 6 it will be seen that the closed end wall 28 of the tubular member 21 is provided with a socket, or recess, 30 therein with which the reduced end 3l of the threaded adjusting member I9 is adapted to engage, said recess, or Socket, 30, thus acting as a bearing for one end of said member I9. It will also be noted upon reference to Fig. 4 that the opposite end wall 32 of said tubular body portion 21 is provided with an opening 33 therethrough, which rotatably receives the unthreaded portion 34 of the adjusting member I9, and that when the parts are in the assembled position ready for use, shown in the drawing, said end wall 32 will be located adjacent the shoulder, or abutment, 24. It will be further noted that the screw-threaded stem I9 is provided with a transverse opening spaced from the shoulder 24, through which the cotter pin 35 extends, said cotter pin being of such size that it will not be sheared off by any strain that may be placed thereon in the operation of the device. It will thus be seen that the tubular member 21 is held from endwise movement relative to the screw-threaded adjusting member, as it will be limited in its endwise movement by means of the abutment 24 and the pin 35. Also it will be noted that the proportion of the parts is such that the reduced end 3l will not extend to the bottom of the socket 3E! when the shoulder 24 engages the end wall 32, thus preventing any binding of the screw-threaded stem I9 between the leg II and the end Wall 28.

It will also be seen that, due to the provision of the slot 29 and the connection between the screw-threaded adjusting member, or screwthreaded stem, I9 and the tubular jaw member 21, the adjusting member will rotate in the bearings 3l and 33 as the same is rotated by means of the handle 22, thus moving the C-shaped body portion of the clamp relative to the tubular member 21 so as to draw the jaw I6 toward the jaw 28 when the handle 22 is tiuned in one direction, and push the C-Shaped body portion in a direction such as to move the jaw Iii away from the jaw 28 when the handle 22 is rotated in the opposite direction. The portion of the stem I9 that lies between the end wall 28 and the ieg I I of the C-shaped body portion has no strain whatsoever thereon in the adjustment of the clamp into clamping engagement, Furthermore the tubular body portion completely shields the screw-threaded stem portion I9 from the heat of` the welding are, or welding flame, when the clamp is used in connection with welding apparatus, for which it is particularly useful, the large body of metal in the tubular body portion not only protecting the screw-threaded member against the direct flame, or are, but dissipating the heat so that there will be no such a high temperature reached at said screw-threads as to in any way damage the same. Also it is noted that the hat faces of the jaws I6 and 28 will always be parallel to each other due to the slidable connection between the C-shaped body portion and the tubular body portion forming the two relatively movable parts carrying the jaws of the clamp.

What I claim is:

1. A clamp comprising a C-shaped frame having a xed jaw on one of the legs thereof, the other leg having a portion provided with a screwthreaded opening, a screw extending through said opening, a longitudinally slotted tubular member having a closed end providing a jaw cooperating with said fixed jaw, the leg having the portion provided with the screw-threaded opening extending through the slot in said tubular member and cooperating with the walls of said slot to prevent rotation of said tubular member relative to said leg, said portion having said screw-threaded opening being mounted within said tubular member, said screw having one end thereof journaled in said closed end of the tubular member, said tubular member having a bearing in the other end thereof for journally receiving the other end of said screw, means to prevent longitudinal movement of said screw with respect to said tubular member, and means on said screw externally of said tubular member for rotating the screw to produce relative movement between said tubular member and said fixed jaw.

2. A clamp comprising a C-shaped frame having a xed jaw on one of the legs thereof, the other leg having a portion provided with a, screw-threaded opening, a screw extending through said opening, a longitudinally slotted hollow elongated member having a closed end providing a jaw cooperating with said fixed jaw,

the leg having the portion provided with the Screw-threaded opening extending through the slot in said hollow member andcooperating with the walls of said slot to prevent rotation of said hollow member relative to said leg, said screw having one end thereof journaled in said closed end of the hollow member, said hollow member having a bearing in the other end thereof. for journally receiving the other end of said screw, and means adjacent said bearing to prevent longitudinal movement of said screw with respect to said hollow member, said portion having the screw-threaded opening engaging said screw between the end thereof that is journaled in the closed end of said hollow member and the means preventing longitudinal movement of said screw relative to said hollow member, whereby said screw exerts a pull on said C-shaped frame upon rotation thereof in a clamping direction and is put under tension only between the means preventing longitudinal movement of said screw relative to said hollow member and the portion thereof engaging said leg when said clamp is in clamping engagement with the work.

3. A clamp comprising a frame having a pair of, legs thereon, a jaw onone of the legs, the other leg having a portion provided with a screwthreaded opening, a screw extending through said opening, a longitudinally slotted tubular member having an end wall providing a jaw cooperating with said first-mentioned jaw, the leg having the portion provided with the screw-threaded opening extending through the slot in said tubular member and cooperating with the Walls of said slot to prevent rotation of said tubular member` relative to said leg, said portion having said screw-threaded opening being mounted within said tubular member, said screw having one end thereof vjournaled in said jaw forming end of the tubular member, said tubular member having a bearing in the other end thereof for journally receiving the other end of said screw, means to prevent longitudinal movement of said screw with respect to said tubular member, and means on said screw externally of said tubular member for rotating the screw to produce relative movement between said tubular member and said firstmentioned jaw.

4. A clamp having a C-shaped body portion providing a pair of spaced legs, a jaw on one of said legs near the .end thereof, the other leg thereof being provided with a screw-threaded opening near the extremity thereof spaced from the portion of the clamp connecting the legs, a member having a screw-threaded stem in screw-V threaded engagement with the threads in said opening, means on said member for turning the same, a substantially straight elongated jaw member extending transversely of said other leg and having bearings therein adjacent the opposite ends thereof on opposite sides of said other leg to mount said elongated jaw member on said member having SaidsCreW-threaded stem, said elongated jaw member having abutment means thereon extending longitudinally thereof and said other leg having means thereon engaging with said abutment means to hold said elongated member to substantially straight line translation axially of said threaded stem upon rotation of said stem, said elongated jaw member having a clamping face on the end thereof of substantially the area of said other jaw and spaced from said connecting portion, and abutment means on said member having the screw-threaded stem cooperating with the end of said elongated jaw remote from said clamping face to put said elongated jaw under compression and the portion of said stem between said leg and the end of the elongated jaw remote from said clamping face under tension when in clamping engagement. with the work.

5. A clamp comprising a C-shaped integral frame having a pair of legs, a jaw on one of said legs, a screw, means on the other leg engaging said screw to advance the same transversely of.

said leg in either direction, a longitudinally lslotted tubular member having end walls, one of said end walls providing a jaw cooperating with said first mentioned jaw, said other leg extending c thereon, the end walls of said tubular member mounting the same on said screw on opposite sides of the leg extending into said tubular member, means limiting longitudinal movement of said screw with respect to said tubular member in opposed directions, and operating means externally of said tubular member for producing relative movement between the screw engaging means on the other leg and the screw to produce movement of said tubular member toward and away from said iirst mentioned jaw, said longitudinal movement limiting means comprising abutment means on said screw engaging the end wall of said tubular member remote fromsaid jaw forming end wall to put said tubular member under compression and the portion of said screw between said leg and the end of said tubular. member remote from said jaw forming end under tension when in clamping engagement with the work.

6. A C-clamp comprising a body portion having a pair of legs integral with and projecting from a connecting portion, a xed yflat'jaw at the free end of one of said legs removed from Said connecting portion, the other leg having a tubular enlargement at its extremity having its longitudinal axis extending'transve'rsely of. said other leg and being internally threaded, clamping means on said other leg having ra flat, rigid clamping face opposite and extending substantially parallel to said flat jaw, said clamping means comprising a screw extending through the opening in said enlargement having threads engaging said internal threads, a longitudinally slottedtubular member receiving said tubular enlargement therein, Asaid slotted tubular member having end walls having means. rotatably receiving said screw beyond the opposite ends of said threads thereon to mount said tubular member on said screw and shield said threads from end to end, said end walls lying on opposite sides of the tubular enlargement on said other leg, said other leg extending through the slot in said tubular member and cooperating adjacent said enlargement with the walls of said slot to limit rotation of said tubular member relative to said other leg, means limiting longitudinal movement of said tubular member relative to said screw, and means on said screw externally of said tubular member .for rotating said screw, said clamping face being of. approximately the diameter of said tubular member, and said entire clamping means being spaced from said connecting portion.

CONRAD J SCI-IROEDER. 

